In this study,endoplasmic reticulum(ER)stress inducer tunicamycin(TM)and inhibitor 4-phenylbutyric acid(4-PBA)were used to treat postmortem chicken breast muscle to investigate changes in tenderness and effects on apo...In this study,endoplasmic reticulum(ER)stress inducer tunicamycin(TM)and inhibitor 4-phenylbutyric acid(4-PBA)were used to treat postmortem chicken breast muscle to investigate changes in tenderness and effects on apoptosis and autophagy during 5 days ageing.TM-induced ER stress reduced shear force,enhanced myofibril fragmentation index(MFI),disrupted myofibril structure,increased desmin degradation,and activatedμ-calpain and caspase-12.In addition,TM-induced ER stress increased the expression of Bax,Bim,and cytochrome c,and decreased the expression of Bcl-x L.Furthermore,TM-induced ER stress improved the conversion of LC3I to LC3II,raised the expression of Beclin-1,and decreased the expression of p62,PI3K,and m TOR.The opposite results were observed after 4-PBA treatment.These results suggested that ER stress could improve chicken tenderness,promote apoptosis and autophagy during chicken postmortem ageing.展开更多
The calpain system is ubiquitous in cells, mainly comprising calpains and calpain inhibitors, and is a widespread calcium-dependent cysteine protease in organisms that is involved in many cellular processes such as mu...The calpain system is ubiquitous in cells, mainly comprising calpains and calpain inhibitors, and is a widespread calcium-dependent cysteine protease in organisms that is involved in many cellular processes such as muscle degradation in vivo and affects the tenderness of meat after animal slaughter. The study found 128 DEGs that probably regulated tenderness traits were selected from 16 significantly enriched GO terms by transcriptome sequencing analysis, and found that the developmental changes in the expression levels of the CAPN1 gene in the pectoral and leg muscles were significantly positively correlated ( P <0.05) with the cumulative growth values of live weight and comb weight. The developmental changes in the expression levels of the CAST gene in the pectoral and leg muscles were not significantly correlated with the cumulative growth values of live weight and comb weight. Our results helped demonstrate the potential molecular mechanisms of tenderness in chickens and provide valuable information for chicken breeding.展开更多
The possibility and rationality of introducing an bid-winning estimate based on a reasonable low price into construction bidding mode with bill of quantities were analyzed by setting up a model for bidding and tenderi...The possibility and rationality of introducing an bid-winning estimate based on a reasonable low price into construction bidding mode with bill of quantities were analyzed by setting up a model for bidding and tendering, and the functions of the estimate of reasonable low price in the bidding were revealed. On this basis, a new bidding mode of the project with bill of quantities was pro- posed. The application of the new mode will be advantageous to the promotion of the bill of quantities in China.展开更多
Since the reform and opening up, the Chinese government has attached growing importance to education, and has invested more resources and funds into higher education. In addition, the government has also invested larg...Since the reform and opening up, the Chinese government has attached growing importance to education, and has invested more resources and funds into higher education. In addition, the government has also invested large amounts of funds and technologies in the infrastructure construction of universities and colleges. The undertakings related to the infrastructure construction of universities and colleges in China are complicated in essence. Therefore, funds and technologies of the highest standards should be introduced. At the same time, external tendering is necessary for some undertakings. Currently, the tendering model adopted by universities and colleges in China is the traditional, which is ridden with some problems to be resolved in the shortest possible period. This paper focuses on the current problems of the tendering model adopted by universities and colleges and their solutions. Taking the tendering model in the undertakings of North China Electric Power University as an example, it notes setbacks of the traditional tendering model, and provides kind of theoretical support for establishing a new tendering model for universities and colleges and the related enterprises in China.展开更多
Ningbo TenderingCenter of Machinery andElectric Equipment wasestablished with the ap-proval by the CompetantState Department andNingbo Municipal Gov-ernment.It is a legal en-tity subordinated to Ning-bo Municipal Econ...Ningbo TenderingCenter of Machinery andElectric Equipment wasestablished with the ap-proval by the CompetantState Department andNingbo Municipal Gov-ernment.It is a legal en-tity subordinated to Ning-bo Municipal EconomicCommittee,specializingin tendering service un-der the supervision,in-spection and guidance ofthe China National Ten-dering Center of Machin-ery and Electric Equip-ment.展开更多
【目的】克隆牦牛丝氨酸蛋白酶抑制剂家族E成员1(serpin family E member 1,SERPINE1)基因序列,同时探究不同嫩度牦牛背最长肌组织中SERPINE1基因核苷酸序列差异,为进一步研究其对牦牛肉嫩度的影响提供试验数据。【方法】根据GenBank中...【目的】克隆牦牛丝氨酸蛋白酶抑制剂家族E成员1(serpin family E member 1,SERPINE1)基因序列,同时探究不同嫩度牦牛背最长肌组织中SERPINE1基因核苷酸序列差异,为进一步研究其对牦牛肉嫩度的影响提供试验数据。【方法】根据GenBank中牦牛SERPINE1基因序列设计特异性引物,通过PCR扩增克隆获得高、低嫩度牦牛背最长肌中的SERPINE1基因序列全长,并对其结构及编码蛋白进行生物信息学分析,通过实时荧光定量PCR检测不同嫩度牦牛背最长肌中SERPINE1基因表达量。【结果】高、低嫩度牦牛背最长肌组织中SERPINE1基因全长分别为8 315和8 318 bp,均编码402个氨基酸且氨基酸序列完全相同。高、低嫩度背最长肌组织中SERPINE1基因非编码序列中存在3个碱基缺失及22个碱基突变(4个碱基颠换、18个碱基转换)。牦牛SERPINE1基因核苷酸序列与普通牛、瘤牛、美洲野牛、绵羊、山羊、家猪、人、小鼠的相似性分别为99.26%、99.26%、99.59%、96.94%、97.02%、90.49%、86.52%和80.10%。SERPINE1蛋白是一个含有23个氨基酸信号肽的亲水性稳定膜外蛋白,位于细胞外,具有34个潜在磷酸化位点,包含1个反应中心环(reactive center loop, RCL)。SERPINE1蛋白二级结构主要由α-螺旋(44.78%)和无规则卷曲(35.32%)构成。实时荧光定量PCR结果显示,SERPINE1基因在高嫩度牦牛背最长肌中表达量极显著高于低嫩度牦牛背最长肌(P<0.01)。【结论】本研究成功从高、低嫩度牦牛背最长肌组织中克隆SERPINE1基因全长并进行了生物信息学特征分析,为后续研究SERPINE1基因参与调控牦牛肉嫩度机制提供理论参考。展开更多
基金supported by the National Natural Science Foundation of China(G32072142,31972099)。
文摘In this study,endoplasmic reticulum(ER)stress inducer tunicamycin(TM)and inhibitor 4-phenylbutyric acid(4-PBA)were used to treat postmortem chicken breast muscle to investigate changes in tenderness and effects on apoptosis and autophagy during 5 days ageing.TM-induced ER stress reduced shear force,enhanced myofibril fragmentation index(MFI),disrupted myofibril structure,increased desmin degradation,and activatedμ-calpain and caspase-12.In addition,TM-induced ER stress increased the expression of Bax,Bim,and cytochrome c,and decreased the expression of Bcl-x L.Furthermore,TM-induced ER stress improved the conversion of LC3I to LC3II,raised the expression of Beclin-1,and decreased the expression of p62,PI3K,and m TOR.The opposite results were observed after 4-PBA treatment.These results suggested that ER stress could improve chicken tenderness,promote apoptosis and autophagy during chicken postmortem ageing.
基金Supported by Science and Technology Support Planning Project of Sichuan Province(2021YFYZ0031SASA2024CZYX002)National Modern Agricultural Technology System Construction of China(CARS-41-G07)。
文摘The calpain system is ubiquitous in cells, mainly comprising calpains and calpain inhibitors, and is a widespread calcium-dependent cysteine protease in organisms that is involved in many cellular processes such as muscle degradation in vivo and affects the tenderness of meat after animal slaughter. The study found 128 DEGs that probably regulated tenderness traits were selected from 16 significantly enriched GO terms by transcriptome sequencing analysis, and found that the developmental changes in the expression levels of the CAPN1 gene in the pectoral and leg muscles were significantly positively correlated ( P <0.05) with the cumulative growth values of live weight and comb weight. The developmental changes in the expression levels of the CAST gene in the pectoral and leg muscles were not significantly correlated with the cumulative growth values of live weight and comb weight. Our results helped demonstrate the potential molecular mechanisms of tenderness in chickens and provide valuable information for chicken breeding.
文摘The possibility and rationality of introducing an bid-winning estimate based on a reasonable low price into construction bidding mode with bill of quantities were analyzed by setting up a model for bidding and tendering, and the functions of the estimate of reasonable low price in the bidding were revealed. On this basis, a new bidding mode of the project with bill of quantities was pro- posed. The application of the new mode will be advantageous to the promotion of the bill of quantities in China.
文摘Since the reform and opening up, the Chinese government has attached growing importance to education, and has invested more resources and funds into higher education. In addition, the government has also invested large amounts of funds and technologies in the infrastructure construction of universities and colleges. The undertakings related to the infrastructure construction of universities and colleges in China are complicated in essence. Therefore, funds and technologies of the highest standards should be introduced. At the same time, external tendering is necessary for some undertakings. Currently, the tendering model adopted by universities and colleges in China is the traditional, which is ridden with some problems to be resolved in the shortest possible period. This paper focuses on the current problems of the tendering model adopted by universities and colleges and their solutions. Taking the tendering model in the undertakings of North China Electric Power University as an example, it notes setbacks of the traditional tendering model, and provides kind of theoretical support for establishing a new tendering model for universities and colleges and the related enterprises in China.
文摘Ningbo TenderingCenter of Machinery andElectric Equipment wasestablished with the ap-proval by the CompetantState Department andNingbo Municipal Gov-ernment.It is a legal en-tity subordinated to Ning-bo Municipal EconomicCommittee,specializingin tendering service un-der the supervision,in-spection and guidance ofthe China National Ten-dering Center of Machin-ery and Electric Equip-ment.
文摘【目的】克隆牦牛丝氨酸蛋白酶抑制剂家族E成员1(serpin family E member 1,SERPINE1)基因序列,同时探究不同嫩度牦牛背最长肌组织中SERPINE1基因核苷酸序列差异,为进一步研究其对牦牛肉嫩度的影响提供试验数据。【方法】根据GenBank中牦牛SERPINE1基因序列设计特异性引物,通过PCR扩增克隆获得高、低嫩度牦牛背最长肌中的SERPINE1基因序列全长,并对其结构及编码蛋白进行生物信息学分析,通过实时荧光定量PCR检测不同嫩度牦牛背最长肌中SERPINE1基因表达量。【结果】高、低嫩度牦牛背最长肌组织中SERPINE1基因全长分别为8 315和8 318 bp,均编码402个氨基酸且氨基酸序列完全相同。高、低嫩度背最长肌组织中SERPINE1基因非编码序列中存在3个碱基缺失及22个碱基突变(4个碱基颠换、18个碱基转换)。牦牛SERPINE1基因核苷酸序列与普通牛、瘤牛、美洲野牛、绵羊、山羊、家猪、人、小鼠的相似性分别为99.26%、99.26%、99.59%、96.94%、97.02%、90.49%、86.52%和80.10%。SERPINE1蛋白是一个含有23个氨基酸信号肽的亲水性稳定膜外蛋白,位于细胞外,具有34个潜在磷酸化位点,包含1个反应中心环(reactive center loop, RCL)。SERPINE1蛋白二级结构主要由α-螺旋(44.78%)和无规则卷曲(35.32%)构成。实时荧光定量PCR结果显示,SERPINE1基因在高嫩度牦牛背最长肌中表达量极显著高于低嫩度牦牛背最长肌(P<0.01)。【结论】本研究成功从高、低嫩度牦牛背最长肌组织中克隆SERPINE1基因全长并进行了生物信息学特征分析,为后续研究SERPINE1基因参与调控牦牛肉嫩度机制提供理论参考。